scholarly journals The Flavonol Isoquercitrin Promotes Mitochondrial-Dependent Apoptosis in SK-Mel-2 Melanoma Cell via the PI3K/AKT/mTOR Pathway

Nutrients ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 3683
Author(s):  
Yeong-Seon Won ◽  
Jeong-Ho Kim ◽  
Rona Camille M. Lizardo ◽  
Hye-Ji Min ◽  
Hyun-Dong Cho ◽  
...  

Isoquercitrin (IQ), a major flavonol present in Prunus mume fruit, has gained much attention in recent studies because of its superior bioavailability and physiological effects. In this study, the anti-cancer mechanism of IQ against human melanoma, particularly its effect on the mitochondria-mediated apoptosis, was investigated. Treatment with IQ at 25 μM concentration effectively inhibited the proliferation of SK-MEL-2 skin cancer cells while the same concentration did not exhibit cytotoxicity against human keratinocytes HaCaT. Morphological analysis and clonogenic assay also showed that IQ can alter the growth and long-term survival of SK-MEL-2 cells. IQ also induced apoptosis in the melanoma cells as manifested in the nuclear morphology changes, DNA fragmentation, increase in the apoptosis rate (17.69% at 25 μM) and accumulation of sub-G1 cell cycle phase population (19.55% at 25 μM). Western blot analysis revealed the involvement of the mitochondrial apoptosis signaling pathway in the anti-cancer property of IQ. Treatment with IQ resulted in the decrease in the levels of procaspase-8 and -9, and Bcl-2 protein, and an increase in the expression of cleaved PARP and Bax. Moreover, AIF and Endo G protein expression increased, indicating a caspase-independent mitochondrial-mediated apoptosis. The anti-proliferative activity of IQ against SK-MEL-2 can also be attributed to the downregulation of the PI3K/AktmTOR signaling pathway. These findings showed that IQ can be developed into a chemopreventive therapeutic agent against the melanoma cells.

2004 ◽  
Vol 24 (16) ◽  
pp. 7003-7014 ◽  
Author(s):  
John C. Wilkinson ◽  
Enrique Cepero ◽  
Lawrence H. Boise ◽  
Colin S. Duckett

ABSTRACT X-linked inhibitor of apoptosis (XIAP) is an endogenous inhibitor of cell death that functions by suppressing caspases 3, 7, and 9. Here we describe the establishment of Jurkat-derived cell lines stably overexpressing either full-length XIAP or a truncation mutant of XIAP that can only inhibit caspase 9. Characterization of these cell lines revealed that following CD95 activation full-length XIAP supported both short- and long-term survival as well as proliferative capacity, in contrast to the truncation mutant but similar to Bcl-xL. Full-length XIAP was also able to inhibit CD95-mediated caspase 3 processing and activation, the mitochondrial release of cytochrome c and Smac/DIABLO, and the loss of mitochondrial membrane potential, whereas the XIAP truncation mutant failed to prevent any of these cell death events. Finally, suppression of XIAP levels by RNA interference sensitized Bcl-xL-overexpressing cells to death receptor-induced apoptosis. These data demonstrate for the first time that full-length XIAP inhibits caspase activation required for mitochondrial amplification of death receptor signals and that, by acting upstream of mitochondrial activation, XIAP supports the long-term proliferative capacity of cells following CD95 stimulation.


2019 ◽  
Vol 20 (3) ◽  
pp. 651 ◽  
Author(s):  
Sang Park ◽  
Dong Kim ◽  
Sunggyu Kim ◽  
Laura Lorz ◽  
Eunju Choi ◽  
...  

Loliolide is a monoterpenoid hydroxylactone present in freshwater algae that has anti-inflammatory and antiaging activity; however, its effects on ultraviolet-damaged skin have yet to be elucidated. This study investigated the antiapoptosis and wound-healing effects of loliolide using HaCaT cells (a human keratinocyte cell line). Loliolide inhibited the expression of reactive oxygen species (ROS) induced by ultraviolet radiation as well as wrinkle formation-related matrix metalloproteinase genes and increased the expression of the damage repair-related gene SIRT1. The apoptosis signaling pathway was confirmed by Western blot analysis, which showed that loliolide was able to reduce the expression of caspases 3, 8, and 9, which are related to ROS-induced apoptosis. In addition, Western blotting, reverse-transcription polymerase chain reaction (PCR), and real-time PCR analyses showed that loliolide enhanced the expression of the epidermal growth factor receptor signaling pathway (PI3K, AKT) and migration factors, such as K6, K16, and K17; keratinocyte growth factor; and inflammatory cytokines, such as interleukin (IL)-1, IL-17, and IL-22 expressed during the cellular scratching process, suggesting a putative wound-healing ability. Because of the antiapoptosis and antiscratching effects on skin of both loliolide and loliolide-rich Prasiola japonica ethanol extract, we consider the former to be an important compound used in the cosmeceutical industry.


2020 ◽  
Vol 9 (7) ◽  
pp. 2074 ◽  
Author(s):  
Hironori Tsujimoto ◽  
Hiroyuki Horiguchi ◽  
Yusuke Matsumoto ◽  
Risa Takahata ◽  
Nariyoshi Shinomiya ◽  
...  

Background: Increasing evidence has demonstrated that postoperative infectious complications (PICs) after digestive surgery are significantly associated with negative long-term outcomes; however, precise mechanisms of how PICs affect the poor long-term survival remain unclear. Here, we focused on the hepatocyte growth factor (HGF)/c-Met signaling pathway as one of those mechanisms. Methods: In the clinical setting, serum HGF levels were measured in the patients with sepsis and those with PICs after undergoing esophagectomy. Using a liver metastasis mouse model with cecal ligation and puncture (CLP), expressions of HGF and the roles of the HGF/c-Met pathway in the progression of tumor cells were examined. Results: Serum HGF levels were very high in the patients with intra-abdominal infection on postoperative days (PODs) 1, 3, and 5; similarly, compared to the patients without PICs, those with PICs had significantly higher serum HGF levels on 1, 3, and 5 days after esophagectomy. The patients with PICs showed poorer overall survival than those without PICs, and the patients with high serum HGF levels on POD 3 showed poorer prognosis than those with low HGF levels. Similarly, at 24 and 72 h after operation, serum levels of HGF in CLP mice were significantly higher than those in sham-operated mice. Intraperitoneal injection of mouse recombinant HGF significantly promoted liver metastases in sham-operated mice on 14 days after surgery. Knocking down c-Met expression on NL17 tumor cells by RNAi technology significantly inhibited the promotion of CLP-induced liver metastases. Conclusions: Infections after surgery increased serum HGF levels in the clinical as well as experimental settings. Induction of high serum HGF levels by CLP promoted liver metastases in a murine liver metastasis model, suggesting the involvement of the HGF/c-Met signaling pathway in tumor promotion mechanisms. Thus, targeting the HGF/c-Met signaling pathway may be a promising approach for malignant tumors, particularly in the patients with PICs.


2019 ◽  
Vol 37 (15_suppl) ◽  
pp. 2585-2585
Author(s):  
Louis Everest ◽  
Monica Shah ◽  
Kelvin K. Chan

2585 Background: Recently, anti-cancer agents have generated excitement due to their capacity to preserve long-term survival in some patients, represented by a “tail of the survival curve”. However, as traditional measures of clinical benefit may not accurately capture long-term survival, amendments to various valuation frameworks have been proposed to capture this benefit. The purpose of this study was to determine how frequently immune checkpoint inhibitor vs. non-immune checkpoint inhibitor anti-cancer agents, displayed trends of long-term survival, as defined by the American Society of Clinical Oncology Value Framework (ASCO-VF) and European Society of Medical Oncology Magnitude of Clinical Benefit Scale (ESMO-MCBS), as well as to analyze the degree of agreement between ASCO and ESMO frameworks. Methods: Anti-cancer agents from phase II or III randomized controlled trials (RCTs) cited for clinical efficacy evidence in drug approval by the Food and Drug Administration (FDA) between January 2011 and March 2018 were identified. Data required for ASCO-VF and ESMO-MCBS were extracted. Difference in how often long-term survival bonuses were awarded were calculated in all RCTs, as well as immune checkpoint inhibitor and non-immune checkpoint inhibitor RCTs individually. Cohen’s Kappa statistic was calculated to evaluate agreement between ASCO-VF and ESMO-MCBS. Results: 100 RCTs were analyzed. RCTs were awarded ASCO-VF version 2 (v2) “tail of the curve” bonuses more often than ESMO-MCBS version 1.1 (v1.1) “immunotherapy-triggered” long-term plateau adjustments (45% vs. 2.6%). Comparing to non-immune checkpoint inhibitor RCTs, immune checkpoint inhibitor RCTs were not more likely to receive ASCO-VF v2 bonuses/ESMO-MCBS v1.1 adjustments (p = 0.32/ p = 0.40). Long-term survival agreement between the two frameworks was poor (kappa: 0.01; p = 0.50). Conclusions: The ASCO-VF v2 and ESMO-MCBS v1.1 may require additional refinement in order to accurately capture the benefit of long-term survival or immune checkpoint inhibitor and non-immune checkpoint inhibitor agents may not preserve substantially different long-term survival populations.


Onco ◽  
2021 ◽  
Vol 1 (2) ◽  
pp. 140-157
Author(s):  
Bruno Takao Real Karia ◽  
Camila Albuquerque Pinto ◽  
Carolina Oliveira Gigek ◽  
Fernanda Wisnieski ◽  
Marilia Arruda Cardoso Smith

Gastric cancer is one of the most common cancers and the third cause of cancer-related death worldwide. The treatment of GC patients improved due to advancements in surgery, radiotherapy and chemotherapy. However, the long-term survival rate of patients with gastric cancer remains around 20%. Thus, development of novel therapeutic approaches is of great interest, in order to reduce the need for mutilating surgeries and morbid adjuvant therapies. For many years, it was believed that the RNA was a mere intermediate molecule in the genetic information flow. However, during the past decades, with the advent of new sequencing technologies, it was revealed that non-coding RNAs play important roles in many different biological processes. The Wnt/β-catenin signaling pathway has been reported to regulate crucial events during neoplasic development, such as cell differentiation, proliferation, invasion, migration, apoptosis, and angiogenesis. In this review, we will focus on microRNAs and long non-coding RNAs that have been implicated in gastric cancer tumorigenesis via modulation of the Wnt/β-catenin signaling pathway, which provided some biomarkers to prognosis, diagnosis, and therapy.


2019 ◽  
Vol 32 (4) ◽  
pp. 193-202 ◽  
Author(s):  
Alicja Gluszko ◽  
Shafaq M. Mirza ◽  
Katarzyna Piszczatowska ◽  
Ireneusz Kantor ◽  
Marta Struga ◽  
...  

Abstract Exosomes, belonging to the group of extracellular bodies, are released by healthy as well as cancerous cells and serve as a communication pathway. Tumor-derived exosomes (TEX) possess the capacity to reprogram the function of normal cells owing to their genetic and molecular cargo. Such exosomes target endothelial cells (among others) in the tumor microenvironment to promote angiogenesis. Blood supply is essential in solid tumor growth and metastasis. The potential of pro-angiogenic changes is enhanced by an increased amount of circulating tumor-derived exosomes in the body fluids of cancer patients. A vascular network is important, since the proliferation, as well as the metastatic spread of cancer cells depends on an adequate supply of oxygen and nutrients, and the removal of waste products. New blood vessels and lymphatic vessels are formed through processes called angiogenesis and lymphangiogenesis, respectively. Angiogenesis is regulated by both activator and inhibitor molecules. Thousands of patients have received anti-angiogenic therapy to date. Despite their theoretical efficacy, anti-angiogenic treatments have not proved beneficial in terms of long-term survival. Tumor-derived exosomes carrying pro-angiogenic factors might be a target for new anti-cancer therapy.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Zsuzsanna Nagy ◽  
Belamy B. Cheung ◽  
Wing Tsang ◽  
Owen Tan ◽  
Mika Herath ◽  
...  

AbstractAlthough selective BRAF inhibitors and novel immunotherapies have improved short-term treatment responses in metastatic melanoma patients, acquired resistance to these therapeutics still represent a major challenge in clinical practice. In this study, we evaluated the efficacy of Withaferin A (WFA), derived from the medicinal plant Withania Somnifera, as a novel therapeutic agent for the treatment of melanoma. WFA showed selective toxicity to melanoma cells compared to non-malignant cells. WFA induced apoptosis, significantly reduced cell proliferation and inhibited migration of melanoma cells. We identified that repression of the tumour suppressor TRIM16 diminished WFA cytotoxicity, suggesting that TRIM16 was in part responsible for the cytotoxic effects of WFA in melanoma cells. Together our data indicates that WFA has potent cytopathic effects on melanoma cells through TRIM16, suggesting a potential therapeutic application of WFA in the disease.


2021 ◽  
Vol 2021 ◽  
pp. 1-14
Author(s):  
Linhao Xu ◽  
Yanli Bi ◽  
Yizhou Xu ◽  
Yihao Wu ◽  
Xiaoxue Du ◽  
...  

Our previous study showed that growth arrest- and DNA damage-inducible gene 153 (GAD153/CHOP) plays an important role in intermittent hypoxia- (IH-) induced apoptosis and impaired synaptic plasticity. This study is aimed at determining which signaling pathway is activated to induce CHOP and the role of this protein in mitochondria-dependent apoptosis induced by IH. In the in vivo study, mice were placed in IH chambers for 8 h daily over a period of 2 weeks; the IH chambers had oxygen (O2) concentrations that oscillated between 10% and 21%, cycling every 90 s. In the in vitro study, PC12 cells were exposed to 21% O2 (normoxia) or 8 IH cycles (25 min at 21% O2 and 35 min at 0.1% O2 for each cycle). After 2 weeks of IH treatment, we observed that the expression levels of phosphorylated protein kinase-like endoplasmic reticulum kinase (p-PERK), activating transcription factor 4 (ATF-4) and phosphorylated eukaryotic initiation factor 2 alpha (p-elf2α), were increased, but the levels of activating transcription factor 6 (ATF-6) and inositol-requiring enzyme 1 (IRE-1) were not increased. GSK2606414, a specific chemical inhibitor of the PERK pathway, reduced the expression of p-PERK, ATF-4, p-elf2α, and CHOP and rescued ER structure. In addition, Bax and Bak accumulated in the mitochondria after IH treatment, which induced cytochrome c release and initiated apoptosis. These effects were prevented by GSK2606414 and CHOP shRNA. Finally, the impaired long-term potentiation and long-term spatial memory in the IH group were rescued by GSK2606414. Together, the data from the in vitro and in vivo experiments indicate that IH-induced apoptosis and impaired synaptic plasticity were mediated by the PERK-ATF-4-CHOP pathway. Suppressing PERK-ATF-4-CHOP signaling pathway attenuated mitochondria-dependent apoptosis by reducing the expression of Bax and Bak in mitochondria, which may serve as novel adjunct therapeutic strategy for ameliorating obstructive sleep apnea- (OSA-) induced neurocognitive impairment.


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